WATER-QUALITY DATA FROM THE GROUND-WATER PROGRAM OF THE SOUTHERN FLORIDA STUDY UNIT OF THE U. S. GEOLOGICAL SURVEY NATIONAL WATER-QUALITY ASSESSMENT (NAWQA) PROGRAM

Four surveys of shallow ground water were carried out in the Southern Florida NAWQA study area from October 1996 through January 1999: a citrus agriculture land-use survey of the surficial aquifer system in Collier and Hendry Counties; a Biscayne aquifer study-unit survey of public-supply wells; a recent residential and light commercial urban land-use survey in Broward County- and a ground-water and surface-water survey of a mixed-agriculture land-use area in southern Dade County.

The files on this web site contain uniformly sampled data of 246 physical and chemical properties of water collected from 109 wells and 11 surface-water sites. The data include physical measurements, major ions, nutrients, organic carbon, radiochemicals, volatile organic compounds, pesticides, and inorganic trace elements. In order to capture the data presented here you will need to cut and paste from the text on the screen to the text processor of your choice running locally on your desktop. Another option would be to shift-click on the link and save the data to a file on your desktop. This method will require you to edit out any extraneous HTML code that you may capture along with the data. If you need further assistance or have a suggestion, please contact the SOFL Database Administrator, Tim Boozer, at (352)237-5514, ext. 212 or use the webmaster email link at the bottom of this page.

Citrus Land-use Survey

Thirty one wells were installed in citrus groves of varying ages, cultivation techniques, and citrus varieties. In addition, 5 wells were drilled in background areas in the same types of soils. Citrus groves in the Florida Flatwoods provinces are intensively drained to prevent inundation of tree roots in the fine silts and sands, however, the water table generally remains about 2-4 feet below land surface. Thus, almost all the wells were less than 15 feet deep. All of the citrus wells were placed within the row in the tree drip line and were sampled once in early summer 1998. Ten wells were selected for a repeat sampling in October and November 1998. The background wells were sampled once.

Study-unit Survey

One well from each of 30 public-supply wellfields in Dade, Broward, and southern Palm Beach Counties was sampled once for all constituents in 1998. Untreated water was collected at the well pump from a faucet used by utilities personnel for sampling. Each well was being pumped at the time of sampling. Well depths ranged from 40 feet deep in the southern end of Dade County to 150 feet deep in Palm Beach County.

Urban Land-Use Survey

The urban land-use survey was set in the central part of Broward County that has residential areas and light commercial parcels less than 25-30 years old in the same vicinity. Thirty-two urban wells and three wells in less-developed areas were sampled once for all constituents from November 1996 through April 1997. Wells were installed in vacant residential properties, parks, golf courses, roadsides, and parking lots.Well depths ranged from 10 to 50 feet deep.

Mixed-Agriculture Land-Use Survey

The C-111 canal drains from north to south through an intensely-culfivated agricultural area between Homestead, Florida and Everglades National Park. In November 1997, the NAWQA team conducted an intensive water-quality study in the C-111 basin to better understand the connection between the shallow ground water and surface water. Surface-water flows were shut off above our study area so that ground water from farms would drain into a reach of the C-111 and C-113 canals and flow downstream through the S-177 structure. We collected water-quality samples for analyses of nutrients, anions, cations, trace elements, pesticides, and volatile organic compounds (VOCS) from seven wells and eleven surface-water sites. Two of the surface-water sites were sampled daily during the four-day drawdown. Average outflow from the basin during the drawdown was approximately 70 to 80 cubic feet per second, or 45-51 million gallons per day. As an additional data source, six public-supply wells in the Homestead area were sampled in January, 1998 for all constituents (see study-unit survey data).